Unroofed coronary sinus and persistent left superior vena cava: a rare neonatal venous anomaly.

Approach to abnormal cardiovascular signs in the early neonatal period is challenging due to delayed fetal adaptation, closure of the patent ductus arteriosus and physiological immaturity. We present a rare case of unroofed coronary sinus (UCS) with persistent left superior vena cava (PLSVC) in a term neonate who presented with recurrent desaturation episodes and persistent oxygen requirements. Transthoracic echocardiography (TTE) revealed this rare venous anomaly, which is mainly reported in the older population and primarily as an incidental finding. TTE with an agitated saline study was the key diagnostic modality. Early diagnosis is crucial given the potential complications of thromboembolic phenomena and brain abscesses. Clinical suspicion should be high in neonates with persistent unexplained oxygen requirements with a structurally normal heart, primarily when associated with PLSVC. This is the first-ever case report of UCS presenting in the neonatal period.